[Changes in the concentration of hydroxyproline in plasma following anastomosis of the intestines].

Hydroxyproline plasma levels were determined in 39 patients before and after operation of the gastrointestinal tract. In the immediate postoperative period a decreased collagen metabolism was detected. From the third and seventh postoperative day respectively a considerable increase of the plasma concentration prevailed to the termination of the measurement period. There was no significant difference in the quantitative change with regard to the type of operation, whereas there were differences in the time course of the reaction. These results support the theory that an injury induces an increase in collagen metabolism leading to an elevation of hydroxyproline plasma concentration.